CoSMIR Performance during OLYMPEX Rachael Kroodsma rachael.a.kroodsma@nasa.gov UMD ESSIC / NASA GSFC OLYMPEX Workshop - Seattle, WA March 21-23, 2017 Kroodsma OLYMPEX Workshop

Kroodsma OLYMPEX Workshop Outline Brief CoSMIR description Instrument characteristics Improvements since IPHEX Performance during OLYMPEX Data outages Issues encountered Data Analysis Geolocation Comparisons with GMI Data Description Kroodsma OLYMPEX Workshop

Instrument Characteristics Conical and cross-track scanning total power radiometer Off-nadir angle 49.2° Similar channels as GMI (high frequency) Frequency (GHz) 50.3 52.8 89.0 165.5 183.31±1 183.31±3 183.31±7 Polarization H V/H Sensitivity (K) 0.42 0.40/0.30 0.80/0.45 0.53 0.43 0.41 Scan Geometry Conical scan Footprint 1.3x1.9 km* Azimuth -60° to 60° (51 samples) 3 seconds to complete scan Cross track scan Footprint 0.8x0.8 km at nadir* Elevation -49.2° to 49.2° (51 samples) 2 seconds to complete scan *DC-8 cruising altitude of 11.8 km Kroodsma OLYMPEX Workshop

Scanning Geometry Two conical and two cross-track scans are alternately performed every cycle with hot and cold target looks after each scan. Cold Cold Scan Direction Cold Cold Conical 2 Hot Crosstrack 1 Hot Conical 1 Hot Hot Crosstrack 2 Scan Direction Flight Direction CoSMIR scan pattern for one complete cycle where the azimuth rotates once and the elevation twice. Corresponding 89V counts shown for a flight. CoSMIR ground track for one cycle. Aircraft ground speed 200 m/s and altitude 11.8 km. Kroodsma OLYMPEX Workshop

Improvements since IPHEX Several modifications were made since the last campaign (IPHEX in 2014) to make CoSMIR more reliable Power system now has a custom board to improve instrument grounding and reduce noise Thermal system now uses chip heaters to better control temperature 166 GHz receiver redesigned with newer technology Mechanical layout redesigned to make it more robust Instrument tested in thermal chamber prior to flight Detected issue with motion control and fixed Kroodsma OLYMPEX Workshop

CoSMIR Performance During OLYMPEX Overall, CoSMIR operated extremely well for most of the campaign Total data collected: 72 hours, 8 minutes Total data lost: approx. 4 hours Nominal operation: all channels operated for entire flight with CoSMIR in hybrid scan mode Cross-track mode only: first three flights operated only in cross-track until azimuth scan was fixed Hot target power supply: issues with power supply on plane caused computer outages and gain increases Some flights lost 52 and/or 50 GHz channels part way Kroodsma OLYMPEX Workshop

CoSMIR data collected (UTC) Date (UTC) CoSMIR data collected (UTC) GPM overpass (UTC) CoSMIR performance notes 11/5/2015 20:04-22:38 -- Nominal operation Engineering test flight out of Palmdale, CA 11/12/2015 16:09-22:17 21:16 Cross-track mode only 11/13/2015 13:56-19:29 11/14/2015 17:13-23:17 21:06 11/18/2015 18:29-00:06 11/23/2015 15:57-21:40 11/24/2015 14:40-19:34 18:36 Hot target power supply issue 11/25/2015 17:24-19:15 17:43 Lost 52 GHz channel after 18:20 due to gain increase 12/1/2015 20:59-01:25 Hot target power supply issue Lost 52 GHz channel after 22:43 Lost 50 GHz channel after 00:15 12/3/2015 14:33-16:59 15:22 Hot target power supply issue Lost 52 GHz channel after 16:05 12/4/2015 13:27-17:31 Fixed hot target power supply issue 12/5/2015 14:18-15:38 15:13 Lost 52 GHz channel after 15:08 Lost 50 GHz channel after 15:31 Lost connection with archive computer at 15:38 12/8/2015 14:08-16:33 17:44-19:24 14:11 Lost 52 GHz channel after 14:36. Lost connection with archive computer at 16:33 Rebooted successfully but hot target temperature not recorded for the rest of the flight 12/10/2015 14:58-15:55 16:34-19:18 Lost connection with archive computer at 15:55. Rebooted successfully but hot target temperature not recorded for the rest of the flight 12/12/2015 15:52-21:15 12/13/2015 13:54-18:15 12/18/2015 04:57-07:04 12/19/2015 01:32-03:22 2:54 Kroodsma OLYMPEX Workshop

Quicklook Plot Example 12/3/2015 Kroodsma OLYMPEX Workshop

Kroodsma OLYMPEX Workshop Some Pictures Credit: NASA NASA DC-8 CoSMIR CoSMIR mounted on DC-8 Credit: NASA Onboard operations 12/4/2015 flight paths Kroodsma OLYMPEX Workshop

Kroodsma OLYMPEX Workshop Geolocation CoSMIR has an azimuth mounting offset. This offset was estimated and confirmed using Google Earth to plot TBs at coastlines. 11/18 flight 11/25 flight 89H TBs at coastlines look accurate Kroodsma OLYMPEX Workshop

GPM Overpass: Comparisons with GMI Channel GMI 89.0 V/H 166.0 V/H 183.31±3 V 183.31±7 V CoSMIR 165.5 V/H 183.31±3 H 183.31±7 H EIA (nominal) 52.8 49.2 49.3 Footprint (km) 4.4x7.2 4.1x6.3 3.8x5.8 1.3x1.9 11/25 clear air flight Kroodsma OLYMPEX Workshop

GPM Overpass: Comparisons with GMI 183.31±3 183.31±7 GMI vs. CoSMIR TBs by channel and date. CoSMIR TBs are averaged over a GMI footprint. Locations of GMI/CoSMIR match-ups Channel 89V 89H 166V 166H 183.31±3 183.31±7 GMI-CoSMIR mean TB (K) 2.2 -0.5 1.9 1.1 3.8 Kroodsma OLYMPEX Workshop

Kroodsma OLYMPEX Workshop Data Description olympex_cosmir_YYYYMMDD_conical_v1.hdf5 olympex_cosmir_YYYYMMDD_crosstrack_v1.hdf5 HDF5 files with 3 groups Aircraft: altitude, heading, latitude, longitude, pitch, roll, speed Interpolated to CoSMIR pixels Cosmir: azimuth, elevation, incidence angle, latitude, longitude, TB Time: year, month, day of month, hour, minute, second, millisecond Quicklook plots also available Kroodsma OLYMPEX Workshop